The ACLU of California wants to crowdsource alleged incidents of police misconduct with an app that lets bystanders download their video directly to the civil rights group before their smartphones can be snatched by the authorities.

“Mobile Justice CA” works on Android and Apple products, and can be downloaded at Apple’s App Store and Google Play. The app lets users record and store audio and video on ACLU servers and file incident reports directly to the group for review.

Mobile Justice also allows the user to send an “alert to anyone with the app, giving them the option to go to the location and document the encounter when police stop someone,” according to the ACLU website.

The ACLU says the app was designed for bystanders, but that those encountering law enforcement can use it too. They do caution against reaching into one’s pocket and whipping out a cellphone before telling the police what you are doing.

“Anyone interacting with law enforcement should announce that they are reaching for a phone, and that they are attempting to access the app to record the exchange,” the ACLU warns. “Users’ safety depends on their ability to clearly communicate any actions they take and remain calm.”

Some would say users’ safety relies, to some extent, upon how the police respond to some a pronouncement, although it is against the law for them to grab and destroy a camera or videographer.

A week ago in Los Angeles County’s city of South Gate, a U.S. Marshal charged at a woman standing on the sidewalk and grabbed her cellphone as she filmed him and others arresting suspects in her neighborhood. The marshal smashed the phone, but didn’t see another woman across the street filming the incident.

The incident is under investigation.

California is not the first state to be offered the app. The ACLU rolled it out in New York in 2012 under the name “Stop and Frisk Watch,” in honor of the city’s aggressive program police street intimidation program championed by Mayor Rudy Giuliani and Chief William Bratton. The app debuted in Oregon, Missouri, Mississippi, and Nebraska last November.